Digital cameras use various image sensors (CCD, CMOS, etc.) to convert light received through optical components (e.g., lenses) into electronic signals. The electronic signals are then sent through on-camera processing pipelines to ultimately generate exchangeable-format images stored on the camera. The images may be displayed on the camera's display screen, and the images may be manually transferred to another device such as a desktop, laptop, tablet or other computing device. The exchangeable-format images are in a device-independent format that may be shared between computing devices, such as JPEG, GIF, etc. The processing pipeline includes an image signal processor (ISP) implemented primarily in hardware within the camera. The dedicated hardware implementation is due to the high computational intensity of the processing operations in the ISP, and enables high quality exchangeable-format images to be generated relatively quickly. The on-camera processing operations may include range correction, defective pixel correction (DPC), lens shading correction, demosaicing, etc.
The inventor has recognized several drawbacks with the typical on-board ISP, discussed above. For instance, implementing the ISP via hardware components decreases the ISP's adaptability and inhibits performance upgrades and processing operation improvements. Additionally, it may take a considerable amount of time to develop improved hardware for on-board ISPs, lengthening the duration for iterative improvement and increasing the time it takes new innovations to reach the market. Moreover, it may be desirable to display an image on the camera with a small amount of lag after an exposure is taken and with a small amount of power expense. On the other hand, it also may be desirable to generate a high quality image, which can increase the complexity of the onboard systems and consume more power. The aforementioned goals (i.e., lag, power expense, and image quality) are usually at odds. Thus, generating images via an on-camera ISP may involve trade-offs between lag, power expense, and image quality.